Weight loss medication: Part I
Weight loss is complex. Weight loss in midlife is particularly difficult. Yet celebrities are shrinking before our very eyes and the newspapers are flooded with stories about weight loss medication. This is intriguing. So, let’s dig in and understand more.
How does the weight loss medication work?
Very simply stated, the weight loss medications are appetite suppressants. They mimic the effects of a peptide which we make for ourselves called GLP-1 (Glucagon-like Peptide-1). We release GLP-1 when we eat and that acts on the receptors in our brains which control our appetite. GLP-1 triggers the feelings of fullness and satisfaction which make us stop eating.
Semaglutide (such as Ozempic and Wegovy) is a synthetic version of GLP-1. Semaglutide activates GLP-1 receptors in the brain which:
reduces hunger signals
increases feelings of fullness and satiety
delays stomach emptying
helps to regulate blood sugar stability.
These factors lead to appetite suppression, smaller amounts of food being eaten, and ultimately (in some, but not all, patients) weight loss.
The Wegovy manufacturer’s step 1 trial (PMID 33567185) demonstrated that after six months around 90% of participants had achieved over 5% loss of body weight. Some participants lost 20% of their body weight. All participants followed a calorie deficit diet and increased physical activity alongside the weekly injections.
Mounjaro mimics GLP-1 and also GIP (Glucose-dependent Insulinotropic Polypeptide). Again, we make GIP for ourselves. GIP supports the appropriate release and utilisation of insulin, the glucose storage hormone.
In the Mounjaro manufacturer’s clinical trials (PMID 38078870), the mean weight reduction was 25% after 88 weeks. The participants were also encouraged to follow a calorie deficit diet and undertake at least 150 minutes of physical exercise weekly.
What happens after the weight loss medication is stopped?
The extension to the Wegovy manufacturer’s step 1 trial (PMC 9542252) found that one year after withdrawal of the weekly injections and lifestyle intervention two-thirds of the lost weight had been regained.
Similarly, withdrawing Mounjaro led to a substantial regain of lost weight (PMID 38078870).
What are the potential downsides to taking weight loss medication?
The Wegovy manufacturer’s website (novomedlink.com) lists a number of warnings and precautions in connection with use of the injections. These include an association between Wegovy and impaired gallbladder function, severe gastrointestinal adverse reactions and potential changes to mood and behaviour. Please raise any concerns which you have with your prescriber.
The Mounjaro manufacturer’s website (lilly.com) lists similar warnings and precautions. Again, please raise any concerns which you have with your prescriber.
From my perspective as a nutritionist and functional medicine practitioner, two big questions arise:
How do you protect your health and vitality when the weight loss medication works and you significantly decrease the amount of food you eat?
How do you maintain the weight loss after you stop taking the weight loss medication?
Let’s address each of these questions in turn.
How to protect your health and vitality when significantly reducing your food intake
Let’s be clear that what we eat determines how we feel, our energy levels, our mood, our resilience. This is because we break down what we eat into amino acids, glucose, fatty acids, vitamins and minerals which we then use to make our energy, to make our bones, to make our neurotransmitters (e.g. serotonin and dopamine) and to support a plethora of other processes which keep us alive and well. Food is our life force.
The first question when taking weight loss medication has to be: what are the “must-eats”? Which nutrients can we not do without? Which foods contain these essential nutrients? How can we get the must-eats in when our appetite has vanished?
Let’s start with protein. There is a real risk that some muscle mass will be lost in addition to fat when taking the weight loss medications described above. This is concerning because we know that muscle mass is a predictor of longevity and essential to metabolic health and that we lose muscle mass as we age (PMID 30048806).
So, how much protein must be eaten?
It is useful to look at the research around an optimal diet following gastric band surgery to get some guidance as to where to start in quantifying the amount of protein to aim for. The post-bariatric surgery research suggests aiming to eat 60-80g of protein daily (PMID 20401543, PMID 35685542). Note that this relates to the protein content of the food, not the weight of the food. So, for example, as a rule of thumb, only one quarter of meat by weight is protein. 1 large egg is only 6g of protein. 200g of chickpeas is 39g of protein - but that is a large volume of food to grapple with when your appetite has vanished.
Getting your must-eats in requires very careful thought and planning. The nutritional value of your plate becomes more important than ever. Putting in this work is essential to your current and future health. I’m going to write more about must-eats in the coming weeks. If you would like my support in working out what your personal must-eats are, please do book a free Zoom call using the button below and we can discuss working together.
How to maintain the weight loss after you stop taking the weight loss medication
Without the weight loss medication, your appetite can return with a vengeance. Maintaining your weight loss also requires careful thought and planning. If you’ve laid the groundwork by introducing enticing nutrient dense foods whilst taking the weight loss medication, you will be much better placed to sustain the win.
Also bear in mind that as your food intake increases again, your digestive system will be put under greater strain. There will be a period of adjustment as your body finds its new normal. It will be time to really work on feeling physically comfortable after you have eaten. There’s much to consider here and which steps you need to take will depend upon where the weaknesses lie in your digestive system. A really good start is likely to be:
aiming to embrace eating and to look forward to your plate of food,
allowing 20 minutes per meal,
chewing your food very thoroughly,
eating in a stress-free environment (no screens, phones, emails or anything else likely to provoke),
leaving gaps between meals to allow the digestive process to complete before you eat again.
Again, if you would like my support, please do book a free 30 minute Zoom call using the button below.
